Thanks to current robotics research, medical robots that can ‘think’ and act independently, or follow a human brain in motion are no longer the stuff of fantasy.

Research is underway in a series of innovative research projects to bring sophisticated medical robot technology to operating rooms at a more affordable price than is currently the case.

Robot-assisted surgery is not a new phenomenon: it first made its way from the research laboratory to hospitals around ten years ago. Constant design improvements have meant that the devices are precise enough today that surgeons can achieve results with minimally invasive interventions. Medical robots have already proven to be invaluable tools in assisting surgeons perform hysterectomies and treat prostate cancer.

But these improvements do not come cheap. A top-of-the-range robot-assisted surgery system unit sells on average today for more than EUR 1.5 million. And during each operation it is employed, thousands more euros will be spent on the additional medical supplies required to complete the surgery. That is why clinics and science institutions are working together to make tomorrow’s robots not just smarter, but more affordable too.

More medical robots to the market

Paolo Fiorini, professor of computer sciences at the University of Verona, Italy, received his first funding for a surgical robots project ten years ago. On seeing how many robotics start-ups struggle to reach commercialisation, Prof. Fiorini became involved in setting up the EuRoSurge project, which pools the talents of seven European universities and clinics to tackle market barriers together.

For the main part, these barriers are financial: in spite of scientists’ recent innovations in robotics, investors have been reluctant to invest in their technological developments until they are assured there will be a market for them.

However, patients and healthcare organisations are showing an increasing readiness to pay extra for robot-assisted surgery, and Fiorini said he is ‘optimistic’ that development costs will soon come down as a result.

‘The surgeon still supervises the operation, but the machine can act alone like a plane in autopilot.’

Private sector involvement is crucial, he said, as research institutes cannot afford the clinical trials needed to bring new medical robots to the market.

Fiorini and his team are working to develop robotics software standards and search engines for patent databases. No single patents database for robotics innovation currently exists and the present format in which robotics patents are presented on the internet makes their access and consultation very difficult.

By ensuring there are software standards and an easily navigable robotics patent system in place, innovations in robotics can also be more appropriately developed and commercialised. Obtaining a patent protects an innovator against the misuse or copying of their idea by others.

Meanwhile, robot-assisted surgery technology has come a long way from the rigid metal structures of earlier days. ‘We’re going from large, heavy systems to small and smart ones,’ said Fiorini. Lightweight and flexible materials open up prospects for producing more versatile machines at a fraction of the cost, with capabilities enhanced using sophisticated new algorithms. ‘You could even use 3D printers to build instruments on demand,’ he said.

Auto-surgeons

The European Union is playing its part in nurturing innovations in the field of robotics by funding several novel robotics research projects. One of them is I-SUR, which is looking to help the health industry automate parts of surgical operations. ‘We’re teaching medical robots to think and act independently,’ said Professor Maarja Kruusmaa of the Center of Biorobotics at Tallinn University of Technology, Estonia. ‘The surgeon still supervises the operation, but the machine can act alone like a plane in autopilot.’

‘Most people, when they are sitting in a plane, do not think that they are flying in an autonomous robot, but they are,’ said Prof. Kruusmaa. And in the same way autopilot in an aeroplane is an example of supervised autonomy, where a pilot can step in at any stage to take over the controls, a robot in an operating room can control itself but a surgeon is able to take over the controls at any time.

This may sound simple, but designing robots to think independently is no mean feat. Current robots are precise when handling stiff materials, but the human body is soft, and difficult for a machine to interpret.

Performing robot-assisted surgery on human tissue, though, is useful not only because machines offer great precision, but also because they can reach and cut out tumours close to vital organs – a procedure that many surgeons still consider too risky to undertake themselves. ‘Machines also do not get tired or distracted,’ said Prof. Kruusmaa.

As a result, I-SUR collaborators are instructing robots to adapt their movements to respond to subtle deformations in organic matter or variations in pressure exerted back on the scalpel. They quantify each surgical task using computer models and compare the results with test subjects built by Kruusmaa’s group.

‘We’ve found a way to engineer gelatine so that it feels, looks and responds to medical imagery like real-life human organs,’ said Kruusmaa. Clinicians have become interested in these gelatine substitutes to train their staff, because they are cheaper than organs harvested from animals or cadavers. The group has now set up a spin-off company to market them.

The changing shape of the human brain

Professor Giancarlo Ferrigno, the coordinator of the ACTIVE project at the Politecnico di Milano, is leading a consortium of companies and universities building a robot capable of conducting brain surgery in motion, following, for example, a patient undergoing an epileptic seizure.

To treat acute forms of epilepsy, surgeons have to remove the affected portion of the brain. ‘The problem is that the brain changes shape throughout the operation, and surgeons cannot update their map of neurological activity because imaging techniques are incapable of following the head of a patient during a seizure. But our robot can follow its motion automatically so that, from the perspective of the surgeon piloting it and for any on-board instruments, the brain will appear stationary.’

Dr Ferdinando Rodriguez y Baena of Imperial College, London, sees bright prospects for ACTIVE. ‘It is ambitious, but I wouldn’t call it science fiction. Head movements during a seizure can reach several Herz. That is fast. But properly integrated software and hardware can track it. The biggest challenge may yet be to follow the relative motion of the brain and the skull.’

He compares the problem to studying a jelly shaken inside an opaque jar. Because of its viscosity, the brain alters its shape and falls out of rhythm with the skull, making it harder to track. But his colleagues are already building a high-resolution model of a ‘deformable brain’, and Ferrigno is considering positioning cameras inside the skull to monitor its position in real time.

In the ACTIVE set-up, a patient’s skull would be mounted during neurosurgery in an ‘active head frame’, unlike at present, where it is usually fixed rigidly to the operating table. ‘The frame would enable the patient’s head to move within a range of positions and orientations around the horizontal plane,’ said Dr Rodriguez y Baena. This way, in the event during surgery of an epileptic seizure or a seizure brought about by electrical stimulation through cortex mapping, for example, a patient’s head could both move and be actively controlled and tracked by the surgeon.

‘Advances in sensors and computing power are what made this revolution in medical robotics possible,’ said Rodriguez. ‘We are only seeing the beginning of what these robots can do.’